My Somfy-SmartThings Integration

So if you are starting on a blank state I would suggest checking these out:

But to answer your question, if using a ZRTSII one channel can control one blind or shade, or a group of blinds or shades. It cannot do both. As an example if you have Blind A and Blind B, Channel 1 can control Blind A, Channel 2 can control Blind B, and channel 3 can control both Blind A and Blind B.